Means for detecting the escape of gas from gas-mains



(No Model.)

. AGUEGUBN. MEANS FOR DBTEGTING THE ESCAPE 0F GAS FROM GAS MAINS.

No. 478,424. Patented July 5, 1892.

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Tu: Nonme persas c o., muro-mno., wnsnmcaow n c UNITED STATES YPATENTOFFICE.

ALPHONSE GUEGUEN, OF PARIS, FRANCE, ASSIGNOR, BY MESNE ASSIGN- MENTS, TOTHE CHARTIERS VALLEY GAS COMPANY, OF PITTSBURG,

PENNSYLVANIA.'

MEANS FORv DETECTING THE ESCAPE OF GAS FROM GAS-MAINS.

SPECIFICATION forming part 0f Letters Patent N0. 478,424, dated July 5,1892.

Application filed April 29,1886. Serial No. 200,597. (No model.)

T0 all whom it may concern:

Bo it known that I, ALPHONSE GUEGUEN, a citizen of the Republic ofFrance, residing at Paris, have invented certain new and usefulImprovements in Means for Detecting the Escape of Gas from Gas-Mains;andI do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same, reference being hadto the accompanying drawings, and to letters ofreference marked thereon,which form a part of this specification.

My invention relates to methods for the discovery of leakage in gaspipes or conduits.

It consists, generally stated, in placing'over a portion of thegas-conduit a layer or body of stones or similar loose solid material,which rests on the conduit and is so covered and surrounded by the earthas to form a'sepa-A rate and isolated chamber or gallery and placing thesame in communication with the at` It also consists in extending saidlayers of bodies of stones continuously over portions of the conduit andisolating them from each other, so forming a series of isolated sectionsor galleries and providing each such section with avent-pipe by whichleakage from'any particular section may be detected and located.l v

It also consists in combining with the gasconduit and the chamber orgallery formed by the layer or body of stones or loose material a tarredcloth or similar cover surrounded and covered by the earth, which willprevent the entrance of dirt into the chamber ergallery and connectingsuch vchamber with the atmosphere by means of the vent tube or tubes.

It also consists in certain other improvements, as hereinafterparticularly setforth.

To enable others skilled in the art to make and use my invention, I willdescribe the same more fully, referring to the accompanying drawings, inwhichmay be connected by joints of ,anyv desired construction, theconduit a shown being connected by the ordinary bowl-and-spigot joint b,packed with lead or other'suitable mate rial.

When my invention is applied to new conduits, I lemploy a thin layer orpacking c of stones over the upper part of the conduit, these stonesbeing generally interposed between the conduit, and a cover d of tarredcloth or paper or other suitable material, and the layer of stonesforming a kind of chamber or gallery in which the gas leaking orescaping from the conduit will collect. In forming this gallery I preferto first saturate a sheet of felt with tar or other heavy oils ofbituminous coal and sand the same interiorly with stones of about theVsize of lentile, so that the felt does not adhere to the side ofthepipes. In this manner a continuous vgallery of two or three millimetersin height is formed over and at the sides of the conduit, within whichthe gas escaping from the leaks necessarily collects, since in order toarrive there they are not obliged to overcome the resistance which the`soil opposes to them elsewhere. The gascollecting galleries are placedin communication with the atmosphere by vent-tubes e, generally placeddirectly over the conduits. These vent-tubes consist of an iron tube thelower partof whichV is screwed into a cylinder or chamber f, of somewhatylargersize, perforated with four small rectangular openingscommunicating with the gallery by means of a bell-mouth g, formed bythevbituminized cloth. The other end of the tube e enters rather freelywith friction into a castiron socket h, following the movements of theground and closed by a removable plug i. The discharge of the gas intothe atmosphere takes place by small horizontal channels made upon theexterior surface of the socket below the top plate of the plug. In thisway IOO the settling of the earth into the escape-orifices is avoided.The gallery may be made in isolated sections, being separatedV by apacking, as at k, or in othersuitable manner, and each vent-tubecommunicates with one of these sections, as shown. lVhen the conduitshave been already laid, the gas-collecting gallery does not exist orleast finds itself very imperfectly constituted by the small shrinkagewhich generally exists between the pipes and the material Iilled in thetrench. It is p then necessaryto increase the number of venttubesemployed and create the gallery each time the occasion presents itself,and in such p cases my invention may be applied in the -followingmanner: The flagstone or other pavement over a surface of about a squaredecimeter is removed, and a hole is dug about fifty centimeters indepth, the hole being as nearas i possible directly over the axis of theconduit.

By means of a eonicaliron screw terminating below in two well-temperedpoints andat the other extremity in a flat iron rod andan iron leverfittingonthe same a hole is bored within this large 'hole down to theconduit, which is then laid `bare by a scoop or other suitable tool.Witlithis method of boring there is no danger of `piercing or crackingthe conduit.

Into the 'hole so made the vent-tube e is then lowered, While disposingas well as possible around its openings large gravel, forming a speciesof chamber, as at Z. space m around the pipe is `filled with earth orclay well stamped, and the tests are taken as `hereinafter described.

that warning will be-given thereof by the odor given out, andas eachvent-tube or passage` communicates with `an isolated section of the`gallerythe probable position of the 'leakiis thus indicated, evenbeneath the most imper-f meablechausse. As the circulation of the airand gases isalways extremely slight in these galleries or chambers, andas the smaller leaks couldbe but poolydistinguished by the sense ofsmell from the vapors and odoriferous ele-1 mentsemanating from thesurrounding earth, in order to render the indicationsmore eliica-` ciousand to recognize the smallest traces of loss which may take place withinthe conduits, an air-pump is applied to the vent-tube by The annularlmeans of an india-,rubber bushing or other- Wise, thereby permitting theexhaustion of the air from the gallery or chamber. The gaseous mixtureis immediately submitted to an analysis to test Whether it containsleakage-gas.

What l claim as my invention, and desi-re to secure by Letters Patent,is-

1. The combination, with an underground gas-conduit, of a layer or bodyof stones or similar loose solid material resting on said conduit andnextending over a portion thereof and so covered and surrounded by earthas to form a separated and isolated chamber or gallery, and a vent-pipeleading from said chamber to thesurface of the ground, through which thegas can escape to the atmosphere, and by which a leakage may bedetectedand located in any particular part of the conduit, substantiallyas described.

2. The combination, with an underground gas-conduit, of layers or bodiesof stones .or similar loose solid material `resting Aon said conduit andextending kcontinuously over `portions thereof and covered andsurrounded by `the earth, such bodies being so separated as to Vform aseries of isolated sections `or galleries, and a ventdetector-pipeleading from each such section to the surface of theground and by whichleakage from Aanyparticular section `may be detected `and located,substantially as set forth.

3. The combination, withan underground .gas-conduit, of a layer or bodyof stones or `similar loose material extending over any-desired portionofthe conduit,.a tarred clothor similar cover extending over `thestonesandV covered and surrounded by earthaand a vent or detector pipeleading from the chamber .so forrned to the surface of theground,substantially as set forth.

Il. The combination, with an .underground :gas-conduit, of a cover oftarred cloth orsimirlar material extending over and on each side of thegas-conduit, and a vent-pipe communi- `eating with the space between thecover `and rthe conduit, substantiallyas set forth.

5. The combination, withfan :underground `gas-conduit, of a vent -pipecommunicating with an enlarged ,chamber `resting onthe conduit, and acover of tarred cloth or similar material extending over said chamberand down the sides ofsaid conduit, substantially `as and for thepurposes set forth.

In testimony whereof I aiiix my signaturein presence of two witnesses.

ALPHONSE eUEcUEN.

Witnesses:

RoB'r. M. HoorER, G. DE MEsTRAL.

IOO

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